A liquid crystal display device in in-plane switching (IPS) mode is known as an example of a display device. The liquid crystal display device in IPS mode comprises a pair of substrates facing each other via a liquid crystal layer. One of the substrates comprises a pixel electrode and a common electrode. The alignment of the liquid crystal molecules of the liquid crystal layer is controlled using the lateral electric field generated between the electrodes. A liquid crystal display device in fringe-field switching (FFS) mode has been put to practical use. In the liquid crystal display device in FFS mode, a pixel electrode and a common electrode are provided in different layers, and the fringe electric field generated between the electrodes is used to control the alignment of liquid crystal molecules.
The following liquid crystal display device has been developed. In the liquid crystal display device, a pixel electrode and a common electrode are provided in different layers. A slit is provided in the electrode closer to a liquid crystal layer than the other electrode. The liquid crystal molecules near the both edges of the slit in the width direction are rotated in opposite directions. The system of this liquid crystal display device is clearly different from the FFS mode, and can increase the speed of response and improve the stability of alignment in comparison with the conventional FFS mode. Hereinafter, the structure of this type of liquid crystal display device is called a high-speed response mode.